Her replacement will be the seventh minister with responsibility for youth policy since 2010, with the role previously filled by Brooks Newmark, Tim Loughton, Edward Timpson and Nick Hurd over the past eight years.

James Cathcart, director of Young Voices Heard, said he is worried that if Crouch's replacement has to take on a similarly large brief that reform of the youth sector will suffer.

Instead, he wants to see the government appoint a dedicated youth minister. In particular he is "very concerned" over the future of a review of statutory guidance requiring local authorities to provide youth services as promised as part of the government's civil society strategy, that was launched by Crouch in August.

As youth minister Crouch also launched the government's loneliness strategy last month. This pledged up to £1.8m to improving community spaces, with a focus on boosting access for young people.

In January she announced £1.7m in funding to support public service mutuals, including those that provide youth services.

Cathcart said: "With the resignation of Tracey Crouch, the government has a challenge and an opportunity.

"The challenge is how do you replace a bespoke portfolio ministerial role with a lead profile on sport, without further diluting and delaying work, which someone new has to grasp on civil society, youth, gambling and loneliness."

"A dedicated [youth] minister would be a smart political move as well as an effective one. The Prime Minister should take her time, take advice and get it right - especially if there is any possibility of an election in 2019."

Matt Lent, chief executive of youth and education charity Future First, also believes Crouch's brief had become too big and wants to see dedicated youth and civil society ministers appointed following her departure.

I think @tracey_crouch was a good Minister who seemed to genuinely cared about her brief, but it became a dumping ground for what Govt consider lightweight issues; sport, civil society, youth policy & loneliness. It's time to give both Civil Society & Youth Affairs f/t Ministers.

"We firmly believe the government should appoint a youth minister who can champion the voices of young people at the heart of government.

"In August the government formally committed to reviewing the guidance which sets out the statutory duty placed on local authorities to provide appropriate youth services.

"The British Youth Council will be seeking reassurances from the Office for Civil Society, ensuring it remains firmly committed to reviewing the guidance set out for local authorities on youth provision."

Crouch's letter to the Prime Minister Theresa May details how she resigned due to the delays related to fixed-odds betting terminals.

"Two people will tragically take their lives every day due to gambling-related problems and for that reason as much as any other I believe this delay is unjustifiable," states her letter.